Counterpoise



April 22, 1952 J. v. FILL 2,593,427

COUNTERPOISE Filed Jan. 23, 1945 FIG.1.

SHROUD LINES AND COUNTEEPOISE [I I7 NJ [6/45 /6-RADlO TRANSMITTER 9ANTENNA lls FIG 2 SYNTHETIC PLASTIC STRANDS H8 smzouo LINE m CDUNTERPOISE INVENTOR. JOHN V. FILL ATTORNEY Patented Apr. 22, 1952 COUNTERPOISE John V. Fill, Miami, Fla., assignor to the United States of America as represented by the Secretary of War Application January 23, 1945, Serial No. 574,161

(Granted under the act of March 3, 1883, as

3 Claims.

amended April 30, 1928; 370 O. G. 757) The invention described herein may be manufactured and used by or for the Governmentfor governmental purposes, without the payment to me of any royalty thereon.

My present invention relates to antenna counterpoise systems, and more particularly, to a combination parachute and counterpoise which, with a radio transmitter suspended therefrom, is adapted to be launched from an airplane.

While not limited thereto, my present invention is particularly well suited to use with the apparatus and in the manner described in the copending application of George F. Wright, entitled Antennas, Serial No. 574,157, filed January 23, 1945, now abandoned.

It has heretofore been proposed to construct the shroud lines of a parachute of wire, so that they could serve the dual functions of supporting a radio transmitter as aforesaid, and provide a part of the antenna system therefor. However, it is found that such shroud lines stretch about when the device is launched, as a result of which said lines snap. Furthermore, said lines tend to become tangled, and so interfere with the proper descent of the parachute.

Hence, it is the main object of my present invention to provide a combination parachute and counterpoise which obviates the foregoing disadvantages by so incorporating the wires of a counterpoise system in the shroud lines of a parachute as to permit said shroud lines to elongate, and absorb the shock resulting from the check on the descent of the equipment when the parachute opens, without the danger of snapping or entangling.

In the accompanying specification there is described, and in the annexed drawing shown, what is at present considered a preferred embodiment of the combination parachute and counterpoise of my present invention. It is, however, to be clearly understood that my present invention is not limited to said embodiment, inasmuch as changes therein may be made without the exercise of invention and within the true spirit and scope of the claims hereto appended.

In said drawing:

Figure l is a side elevational view of a parachute with a radio transmitter suspended therefrom, said parachute incorporating combined shroud lines and counterpoise wires in accordance with the principles of my present invention; and

one of said combined shroud lines and counter- 2 1 poise wires, with the outer covering of the line broken away to show the inner construction.

Referring now more in detail to the aforesaid preferred embodiment of my present invention, with particular reference to the drawing illustrating the same, the numeral 5 designates a parachute, and the numeral 6 designates a radio transmitter.

The parachute includes a canopy 'l and a plurality of associated shroud lines 8, and the transmitter includes an antenna 9 and a counterpoise lead H).

The shroud lines converge in the usual manner, and connect with a suitable metallic lug II, the transmitter being suspended from said lug, and having its counterpoise lead electrically connected thereto.

As best shown in Figure 2 of the drawing, each shroud. line comprises a braided sheath [2, enclosing a core which includes a plurality, here shown as four, of cords 13. The sheath and the cords are preferably made of an elastic material. The material chosen was a dielectric plastic adapted to withstand tensile shock by means of elastic elongation. This plastic, commonly known as nylon, belongs to the family of synthetic linear high polymers known as polyamids produced by the reaction of hexamethylene diamene and adipic acid. Various preparations of this material under some conditions exhibit elongation, within the elastic limit, of as much as 40 per cent. One of said cords has spirally wound thereon stranded copper wire I4 electrically connected to the lug I I.

Because of the manner in which the wire I4 is wound, the shroud lines 8 can stretch when the device is launched without danger of the wires incorporated therein snapping or becoming tangled, thereby eliminating the disadvantages of the prior art as set forth in earlier portions of this specification.

This completes the description of the combination parachute and counterpoise of my present invention. Objects and advantages thereof, other than those specifically referred to herein, will be apparent to those skilled in the art to which the same relates.

I claim:

1. In combination with aerial suspension means having depending shroud lines for supporting a radio transmitter, an antenna counterpoise system comprising: electrical conductors spirally wound about said shroud lines and a terminal lug electrically connected to each of said conductors and to said radio transmitter.

2. In combination, aerial suspension means having shroud lines connected thereto, a radio transmitter suspended from said shroud lines below said aerial suspension means and including an antenna, said shroud lines being comprised of an elastic dielectric, and electrical conductors helically wound around certain of said shroud lines in such manner as to be jointly co-extensible therewith, and being electrically connected to said transmitter so as to form an antenna counterpoise.

3. In combination, aerial suspension means having depending shroud lines, a radio transmitter supported by said shroud lines, an antenna for said transmitter extending therefrom, said shroud lines extending laterally of said antenna and comprising elastic dielectric strands, and electrical conductors wound around certain of said strands so as to be extensible therewith,

said electrical conductors being electrically con- 2 nected with said transmitter and forming a counterpoise for said antenna.

JOHN V. FILL.

REFERENCES CITED The following references are of record in the file of this patent:

5 UNITED STATES PATENTS Number Name Date 1,296,687 Nichols Mar. 11, 1919 1,540,998 Plauson June 9, 1925 10 1,557,389 Todd Oct. 13, 1925 1,780,369 Snow, Jr. Nov. 4, 1930 2,151,336 Scharlau Mar. 21, 1939 2,281,284 Hammond Apr. 28, 1942 2,293,949 Potter Aug. 25, 1942 15 2,354,086 Mackay July 18, 1944 2,366,423 Pear, Jr. Jan. 2, 1945 2,456,015 Orser Dec. 14, 1938 FOREIGN PATENTS 0 Number Country Date 245,533 Great Britain Jan. 14, 1926 225,204 Germany Aug. 19, 1910 232,257 Germany Mar. 10, 1911 

